Arm rest



FIG. 1 is a front perspective view of an arm rest according to my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a rear elevational view thereof; and,

FIG. 5 is a top plan view thereof.

The broken lines in FIGS. 1, 2, 3, and 4 are for the purpose of illustrating environment and form no part of the claimed design. 

We claim the ornamental design for an arm rest, as shown and described. 